WHAT a deeply depressing week for those of us who yearn for a sensible debate about immigration – so thank God for the guy in the dog collar.

The past few days have seen the Conservatives and Labour battling to be the tough guy, with thunderous talk of ripping up the EU’s founding rules, of “crackdowns”, towns “swamped” and of “red lines”.

Defence Secretary Michael Fallon was ticked off by his boss for the “swamped” remark – but No.10 appeared perfectly happy that he also claimed towns are “under siege”.

We then learned the Government’s policy towards refugees fleeing war-torn North Africa in rickety boats across the deadly Mediterranean. It is: “Let them drown.”

On the Labour side, Ed Miliband flexed his muscles by pledging a fast-track Immigration Bill that will focus on “stronger controls on people coming here”.

Yes, Labour also wants to end the “exploitation of migrant workers that undercuts local workers” – a welcome recognition that it is our loose regulations that cause so much damage.

But you will search in vain, on Labour’s website, for a single word celebrating the benefits of immigration, the immense contribution to our country, or seeking to squash any of the hysteria about the issue.

Does it mention this year’s study which found “migrant entrepreneurs” have created 464,527 firms – one in seven medium-sized companies – and countless jobs? Of course not.

Then, yesterday, we had the ridiculous spectacle of Mr Miliband spending Prime Minister’s questions accusing David Cameron of having “failed” on his target to slash net migration target.

Yes, he has “failed”, but because it was the most stupid target ever created, in an EU with free movement – something most Conservatives privately concede. Why not point that out?

All this wrist-slashing exchange achieved was to fuel the fantasy that immigration is out of control and that mainstream politicians can’t, or won’t, do anything about it.

As a clever colleague put it: “‘You can't control immigration!' 'No, YOU, can't control immigration!' Somewhere, Nigel Farage is lighting a cigar.”

The contrast with the guy in the dog-collar – otherwise known as the Archbishop of Canterbury - just two miserable days earlier, could not have been starker.

The former Bishop of Durham spoke to the press gallery, revealing that his clergy are witnessing soaring levels of racist abuse across the country.

The Most Rev Justin Welby said, of rabble-rousing politicians: “Do I worry about the language? Yes I do, I really do.

“We're seeing is an upsurge in minor, racist, anti-Semitic, anti-Islamic, anti-foreigner, xenophobic comments, which for the people from those backgrounds is really quite frightening.”

He also ridiculed the idea that immigration is “a deep menace that is somehow going to overwhelm a country that has coped with many waves of immigration and has usually done so with enormous success”.

Can the Archbishop be persuaded to cross the River Thames, swapping Lambeth Palace for the one for MPs, here at Westminster? Justin, you’re sorely needed!

AS it happens, Mr Welby talked about crossing the river to visit the Foreign Office, while William Hague was in charge – surprising the Richmond MP by revealing he turned down a car.

Mr Hague said: “So you walked across the river?” prompting the reply: ‘I usually do, but my staff say it’s showing off.” Yes, he tells jokes as well.